US1617024A - Color chart - Google Patents

Description

'Feb. 8 9

A. E. O. MUNSELL ET AL COLOR CHART Filed March 24, 1923 2 Sheets-Sheet 1 Feb. 8, 1927; I 1,617,024

. A. E. o. MUNSELL ET AL;

COLOR CHART Filed March 24, 1923 '2 Sheets-Sheet 2 [fa tented: Fa. 8,1921.

UNITED 'SZTATES' A H 1, 17,024. PATENT: OFFICE;

n. 0. menu, or ammonia, mum, AND mmon E. norm, or

or nnwxonx; n. Y., a conrona'rron or nnwyonx. I

.ooLon. cnan'r.

Application flled l arch 24, 1923. se ial No. 21.5 5.

- This invention relates generally to color charts. Colorcharts have been resorted to past for educational. as .well as practical i purposes. They serve-,to ,either exhibit known colors for selection or present .different' colors for comparisonor establish orderly relationships or determine "secondary and tertiary colors from 'primary colors. Our invention has as its-general object a colort'chart which contains on a 's'inglesurface all 'known or conceivable colors and means for selectively correlating difi'erent colors represented on the chart. It is apa'rticular 'bject to provide a simple means of attaining harmonious color combinations, based on certain fundamental laws of color harmony, without needless expenditure -of time and energy in the 0 almost fruitless attempts according to the usual-wasteful trial and error method. This-invention is essentially based upon the laws of color of A. H. Munsell as set foath'in the Patent No. 824,374, and upon 5 the truth of these laws- According to the disclosure in the patent .all lmown or conceivable colors have definite lociin a color sphere. The locus of each color is therefore a point in a polar co- 0. ordinate or an orthotomic co-prdinate system.

Each color has three definite characteristics or indices, an-index-of value, an index of chroma and an index of hue. I It is the more specific object of this insj'vention to present all colors known or conflceivablewithin the disclosure of the Muns'ell patent'on a single surface. and to provide acilitles fonexhibiting any desired plural-- lay of colors whichJre in an orderly, char- O acteristicig peculiar correlationship in the theoretical color" sphere suggested in the atent; f i a f Itlfis another special-object to provide a color chart for exposing for-com ,parison off-the colors' shown areas which are mversly lilrlrportionalf to" their [respective indices of c j ma, or to their indices ofvalue, or pre erablyboth. The chart of Figure 1 being [of this preferential-form, the radii of the concentric circles increasing outwardly and the angle-between'the radial also increasing clockwise to an extent in each case suflicient to produce a chart of. the preferential form.

from the description and tion;

-Other more specific objects will appear companying it.

In the drawings,

Fig. 1 is a plan view of a color chart, represented on a reduced scale, indicating in a general way the principle of applica-- Fig. 2 1s diagrammatically another from of chart; Fig. 3 is an elevation of a chart to that shown in Fig. 1 and a mask for seleca plan view showing more or less ROCHESTER NEW YORK, ASSIGNOBS TO MUNSELL COLOR GQMPANY, INQORPO- the drawings actively exposing a plurality" of colors correlated in some particular manner; and,

a Fig. 4 is a plan view thereof.

' Having reference to Fig. 1, the chart is subdivided by a large number of radial lines 11 into small sectors which preferably termi- I hate outwardly in a circle 10 and inwardly a distance from the'center 0 in a circle 12.

For reasons to be more fully explained, the

chart disclosed has five principal sectors 7 containing each fourteen radial There are also n ne concentric circles 13 niter mediate the periphery and the circle 12 which divide the chart into ten annular spaces. The radial lines 11 and the'circles .13 by their intersections divide the whole area intermediate the peripheral circle 10 andzthe circle 12 into-seven hundred small areas or facelets. J As is clearly indicated, in each of the five principal sectors the radial lines 11 are spaced increasingly farther a art in pairs in clockwise direction, i. e; the or the third and fourth, or the fifth and sixth and second,

facelets etc. within the same two adjacent circles are substantially thes'ame. The width ofthe facelets from circle is self-vident.' As above 10- toward the circle 12 gradually decreases, a

mentioned, according the A Muns ell'system, colors are classified according to hue (dominant wave length), chroma (wave lengthipuri and value total reflection-of white li t).

It hasbeen foun 's'uflicient and practical so far to subdivide chroma into no. more." than ten degrees, and value into seven derule, i. e. with the exception of grees in order to cover all distinguishable r and greatest near the middle.

- prises ten degrees.

- porary, since new pigments or dyes may be found which will occupy spaces situated out side of the stepped line 14.- (centrally in relation to the stepped line 14),; for example, in Fig. 1 the radial segment'marked R includes four facelets marked respectively l, 2, 3 and 4. The fact that in this radial segment the. facelets 1, 2, .3 and 4 are included within the stepped line 14 and facelets 5, G, 7, 8, 9 and 10 lie outside of the stepped line 14: indicates that up to the presentsamples of red on the eighth level of value cannot be produced in pigment or dye form beyond the fourth step, of chroma. However in the future shouldpigments or dyes be discovered' that will depict tchromas stronger than step 4, the. chromasteps outside of the stepped line 14 maybetfilled in}; The other boundary circle .12v represents'fthe.limit .ol

the sensationsthat :c'anbe experienced the eye. 1

Of greatest importance in color study as well as in practical work ,is the correlation of complementaryjcolors, as is-well known.

It is 'a general 'desideratum to have each 3 color placedfin}juxtaposition with its comple nentaryycolor so as to afford close observation'side by. side... For this reason we prefer toiplace adjacent to a series of colors ofx th'e' same value the-corresponding series of complementary colors. .Thus each of the principal sectors is composed of seven radial rows of two complementary colors alternat- 10 and include red (R), yellow-red (YR),

yellow (Y), green-yellow (GY), green are arabic numbers.-

ing with one another. e e The colors are marked along the circle blue-green' (BG), blue (B), purple-blue -(PB), pu rple' (P) and red-purple (RP).

owever, instead of arranging them according to their position in the order in which they followeach other in the spectrum, we place the complementary colors into one and the same principal sector in alternating rows as mentioned. Thus red and blue green (R) (BG) are in the first sector; blue and yellow-red (B) (YR) in the second sector; ellowandpurple blue (Y) (PB) in the thirdv sector;- purple and green-yellow (P) vGrY) in the fourth sector; and green and red-purple (G) (RP) inthe'fifth sector.

The indices of value as. well as'of chroma v The indices of value vary along the circles and the indices of arrangement. The first' ra'd chromas vary. along radial-dines. "Each color is therefore'identifiedby 'letter at the end of each radialirowand' bywits posi-- tion along the circlespandlalong' the. radial lines. For the sake ofillustratid umerals are marked onthe faeelets t e e left in each principalsector Includes. the

range of chromal of the highestwvalue'of a color. The third, lfifth, etc, rows contain li'cate the ranges of chroma of decreasingly-smalleI values. The second,.fourth, etc. rows con- -tain the corresponding ranges of chroma of the complementary color. Higher numbers mean a higher index. Thus the number 8- represents the highest value, and the number 10 signifies the highest chroma.

The -nun'1bers"l on the otherh'and denote e,

vantage that every degree of chroma of ev.

ery hue is contiguous and in closest juxtaposition to the like degree of chroma of us opposite or complementary hue. onthe same, 'value level.

It is generally understood that higher values of a color have a greater stimulating effect than lower values. The lighter the and the darker'the shade, the smaller is the tint, the greater is the sensation of light,

light effect. Similarly the purer the color,

i. e. the higher the chroma,the greater i the stimulati e By increaslng in ,each

principal sector the areasof,thefffaceletslfrom left to right, the.

higheri values. cover "smaller area than the lower ,v'alue sf Similarlyithe' areas of] higher chroma are smaller than, the areas of lower chroma; Bythelproper selection of the dis tance' between the center. 0 and the' circle 12 andbetween theftwo circles. 10 and 12, and

by properly grading the distances between. radial lines along' the circles, the stimulat} ing effect of any two colored areas .may be substantially equalized. This effect. is of considerable importance for the purpose of making comparisons as to harmony or pleas ing effect of combinations. The predominant effect of one color upon the retina more or less drowns the efiect of the other color. The greater the contrast. in regard to value and chroma, the more overpowering is the effect of the one at the expense of the other and the more one-sided and unreliable is the comparison; By vthe'arrangement proposed conditions are reduced, so to speak, to standard, and permit comparison under ideal conditions;

The arrangement has another important practical result. Aside from facilitating a.

reliable comparison, it affords in .itself a measure of relative areas that may besafely brought into combination to produce :1. pleas ing effect. For the same reason that a relas tively smaller area of a strongercolorf (high value, high chroma, or both) is necessary to balance with a larger areal of a weaker color, for the samereason is advisable to use smaller areas of a stronger color with larger areas'of a weaker color, preferably in the proportion of their combined indices, in

practical application.

Another advantage of the arrangement is the position of'a color relatively close to the two components of its complementary color.

Thus the sector containing yellow is -flanked on one side by blue and on the other side by purple wh'ch are the components of purple-blue this latter being the complementary of yellow and in juxtaposition therewith, as previously explained.

The close spatialprelation of a color, its complementary, and 'its split complements thusbrings conveniently before the eye all or any of those colors which are most closely correlated as regards color harmony and the color-esthetic sense.

In pract ce we propose to use suitable 7 masks, as indicated, Figs. 3 and 4, for selec-.

tively exhibiting any plurality of individual colors, or series of colors, while excluding the other colors from View. We are fully aware that masks are generally not new, and We do not claim any novelty except in so far as masks serve to carry out the object of the specific invention described.

As indicated in Figs. 3 and 4, the mask is preferably slightly smaller than the chart,

and is pivotally mounted thereon. While there 'is considerable latitude in regard to the-detail construction, we prefer to perma- "nently mount a pivot 16 on" the chart and provide a-bear'ng, such asa simple eyelet marked adjacent the exposure openings.

We have .illustrated'a simple and almost primitive'form of mask to illustrate the general operation. A plurality of masks and in fact alarge number of masks may be pro-v vided for selectively exposing particular colors desired to be compared or for expos ing for educational purposes a plural ty of colors correlated in an orderly way by laws of color physics. We contemplate particularlythe useof a plurality of masks for illustrating color relations which are based on the Munsell conception disclosed in the Patent No. 824,374.-, but have not been adequately demonstrated therein. 'By means of special masks it is possible "to simultaneously expose all colors which would beexposed by a section through the spherfcalcolor solid assumed in the'patent. It is thus-possible to expose all colors obtainedby any of a plurality 'ofhorizontal sections, vertical sections oblique sections, or other sections'determining ships.

. We are, of course, fully aware, that within.

the scope of mechanical skill and the light of the state ofthe art masks may be pro vided which admit of changing, shift'ng or otherwise adjusting parts on the mask to expose different colors or different relations by means of the same mask. Our invention, however, is not concerned so much with the particular or peculiar relation numerous detail constructions feasible with-r in its scope as rather with the broader aspect of opening up to the public, teachers, pupils and artists the broadest vista'= into the color realm, and for developing and systematically training the .color-esthetic sense which has strangely not been developedfinthe masses since and notwithstanding the classic times of old Greece, or the period of Renaissance which-did not react upon the general public.

- In Fig. 2 we have diagrammatically indicated that the colors may be linearly arranged instead of in a circle. In fact the single surface for exhibiting the colors may be .any plane surface or a cylindrical, con'cal or.. spherical or any other symmetrically curved.su'rface upon which a mask may be moved to expose any color or plurality of colors desired.

The description of the stepped line 14 in Figure 1 explains the heavy-stepped line in Figure 2, with the understanding that the faceletsin Figure -1 situated outside the stepped line should be referred to on Figure I 2 as situated below the stepped line 1 1.

' In the foregoing, the subdivision of value into seven steps or degrees, and of chroma into at most ten steps, has been adopted as best suiting the sensitiveness of the eye. However, m principle any greater or smaller lit) number. of steps may be adopted. The se- I lection of the number of steps, the s'ze of the chart is only a matter of relativity.

v In regard to the practical aspect of the color chart, it is intended to simplify certain operations of color synthesis which are based upon well known laws.

The hues are marked along line 10 and each hue mayad-va-ntageously carry its index of value as shown in Fig. 1. Each I mask may advantageously mark the .index of chroma of an exposed color. Therefore,

then each color exposed is identified by its hue, chroma and value.

It is often necessary to find the quantities of two colors to produce a balance in neutral gray The chart indicates at once the respective quantities necessary. In' case of .complemtzntary colors of the same chroma andthe same value, the quantities are equal, as. is avell understood. This is also indicated on the chart, since the respective products of the index of chroma and the indexof viously the relative angular arrangement of the colors may be changed in various ways without fundamentally deviating from the principles and the objects of the invention.

\Ve are also fully aware that areas of different colors may be exposed in inverse proportion of their respective chromas or. in other ways than lllUS- values, or both, trated. Ve therefore do not intend to be limited to the particular way shown and described.

Ve claim:

1. A color chart bearing colors of different chroma and means for presenting differ- :ent color areas which differ inversely as their respective chromas difier.

A- color chart bearing colors of differ: ent value and means fpr presenting different color. areas which differ inversely as their respective values differ. I I

3. A color chart bearing colors of different value and chroma and means for presenting different color areas which differ inverselfy as their respective values 'and chromas di .fer.

4. A'color chart bearing colors of different hue, chroma and value and means for presenting different color areas which differ inversely as their respective values and chromas differ.

5. A color chart comprising a plurality of juxtaposed rows of areas bearing the colors of two complementary hues graduated ac-v cording to value and chroma, the arrangement being such that the opposite colors of lllif, value and chroma lie -adjacent each ot er.

6. A color chart comprising a plurality of modifications of, which the arrangement is susceptible. Ob-' juxtaposed rows of areas bearing the colors of two complementary hues graduated according to value and chroma, the arrange ment being such that alternate rousbear.

colors oflthe same hue but of progressively varying value and that the colors in each row progressively vary in chroma.

7. A color chart comprising a plurality of juxtaposed rows of areas bearing the colors of two complementary hues graduated according to value and chroma, the areas Varying in size in inverse proportion to the value and chroma of the colors they bear.

7 S. Arrangement according to claim 7 in which the opposite colors of like value and chroma lie adjacent each other.

bearing each a principal color .and the color (it) I 9. A color "chart containing colors corre- I spondmg to the different colors of the spectrum and comprising a plurality of sections complementary thereto, graduated according.

'- to value and chroma.

. 10. A color chart containing colors corre sponding to the different colors of the spec-' trum and comprising a plurality of sections each bearing a principal color and the color complementary thereto, graduated according to value and chroma *and means for expos-.

ing of a plurality of color "areas which differ-inversely as their respective values and chromas differ.

- 11'. Acolo'r chart comprising five sections.

each" bearing a-principal color and the color complementary thereto, each section having a plurality of rows of alternately opposite hue and of progressively varying value,

and each row bearing colors of progressively varying chroma. A

12. A color chart containing colors corre sponding to the different colors of the spectrum and comprising a plurality. of sectionsv bearing each a principal color and the color complementary thereto, each section having aplurality of rows of alternately opposite hueand of progressively var ing value and each row bearing colors 0 of color areas which differ in-- versely as their respective values and chromas differ. p 1

In testimony whereof, We affix our signatures.

- ALEXANDER E. O. MUNSELL.

MILTON E. BOND.

progressively varymg chroma, and means for exposing of a plurality

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